Brunswick Steam 

Electric Plant

2009 Biological 

Monitoring Report

Environmental Services Section

Cape Fear River Estuary
BRUNSWICK STEAM ELECTRIC PLANT 

2009 BIOLOGICAL MONITORING REPORT 

Prepared by: 

 Environmental Services Section 

 Progress Energy Service Company, LLC 

 Raleigh, North Carolina 

March 2011 
Brunswick Steam Electric Plant 2009 Biological Monitoring Report 

 

Progress Energy Service Company, LLC i Environmental Services Section

Preface

This copy of the report is not a controlled document as detailed in the Biology Program 

Procedures Manual and Quality Assurance Manual. Any changes made to the original of this 

report subsequent to the date of issuance can be obtained from: 

 Director 

 Environmental Services Section 

Progress Energy Service Company, LLC. 

410 South Wilmington Street 

Raleigh, North Carolina 27601 
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Progress Energy Service Company, LLC ii Environmental Services Section

Table of Contents

 Page 

Preface ................................................................................................................................. i 

Table of Contents.................................................................................... ii 

List of Tables ...................................................................................................................... iii 

List of Figures ..................................................................................................................... iv 

List of Appendices .............................................................................................................. v 

Metric-English Conversion and Units of Measure ............................................................. vi 

Common and Scientific Names of Species Used in this Report ........................................ vi 

Executive Summary ............................................................................................................ vii 

1.0 INTRODUCTION ............................................................................................... 1-1 

2.0 MONITORING PROGRAM RESULTS ............................................................. 2-1 

2.1 Introduction .......................................................................................................... 2-1 

2.2 Methods................................................................................................................ 2-1 

2.3 Results and Discussion ........................................................................................ 2-2 

2.3.1 Water Quality ....................................................................................................... 2-2 

2.3.2 Dominant Species ................................................................................................ 2-3 

2.3.3 Seasonality and Abundance ................................................................................. 2-4 

2.3.4 Fine-Mesh Screens and Cooling Water Flow ...................................................... 2-5 

2.3.5 Survival Estimates ............................................................................................... 2-6 

2.4 Summary and Conclusions .................................................................................. 2-6 

3.0 REFERENCES .................................................................................................... 3-1 
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List of Tables

Table Page 

2.1 Annual mean density and percent of total for the ten most abundant taxa 

 collected during entrainment sampling at the Brunswick Steam Electric 

 Plant during 2008 and 2009 ................................................................................. 2-8 

2.2 Total number of the ten most abundant taxa estimated for larval impingement 

sampling at the Brunswick Steam Electric Plant during 2008 

and 2009 ............................................................................................................... 2-9 

2.3 Total number, total weight, and percent of total of the ten most 

abundant juvenile and adult organisms collected in the 

 Brunswick Steam Electric Plant impingement samples during 2009 .................. 2-10 

2.4 Entrainment densities of selected taxa at the Brunswick Steam Electric 

 Plant during 2009 ................................................................................................. 2-11 

2.5 Entrainment rates of selected taxa at the Brunswick Steam Electric Plant 

 during 2009 .......................................................................................................... 2-12 

2.6 Estimated total number of selected taxa collected with monthly larval 

impingement sampling at the Brunswick Steam Electric Plant during 2009 ....... 2-13 

2.7 Density and modal length for selected species collected with juvenile 

 and adult impingement sampling per month at the Brunswick Steam 

 Electric Plant during 2009 ................................................................................... 2-14 

2.8 Mean density and biomass of selected juvenile and adult organisms indicating 

reductions in density and biomass impinged during 2009 as a result of the 

 Fish diversion structure. ....................................................................................... 2-15 

2.9 Percent effectiveness of fine-mesh screens in reducing the number entrained 

 per day for selected taxa at the Brunswick Steam Electric Plant 

 during 2009 .......................................................................................................... 2-16 

2.10 Estimated numbers and percent survival of selected larval organisms 

collected during impingement sampling at the Brunswick Steam Electric Plant 

during 2009 .......................................................................................................... 2-17 

2.11 Estimated numbers, biomass, and percent survival of selected juvenile 

and adult organisms collected during impingement sampling at 

the Brunswick Steam Electric Plant during 2009. ............................................... 2-18 
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List of Figures

Figure Page 

1.1 Location of the Brunswick Steam Electric Plant near 

Southport, North Carolina .................................................................................... 1-3 

1.2 Location of the fish diversion structure, fish return flume, return basin, and 

 sampling locations at the Brunswick Steam Electric Plant during 2009 .............. 1-4 

2.1 Mean daily freshwater flow to the Cape Fear Estuary and monthly intake 

 canal salinity at the Brunswick Steam Electric Plant during 2009 ...................... 2-19 

2.2 Mean annual freshwater flow to the Cape Fear Estuary, 2005-2009 ................... 2-19 

2.3 Mean monthly intake canal water temperature at the 

 Brunswick Steam Electric Plant during 2009 ...................................................... 2-20 

2.4 Mean winter and summer intake canal water temperatures 

 at the Brunswick Steam Electric Plant, 2005-2009 ............................................. 2-20 

2.5 Number of taxa collected in entrainment and larval impingement 

 samples at the Brunswick Steam Electric Plant during 2009 ............................... 2-21 

2.6 Annual number of total organisms entrained at the Brunswick Steam 

 Electric Plant and percent reduction from baseline entrainment estimates, 

 1979-2009 ............................................................................................................ 2-22 

2.7 Annual number of total organisms entrained at the Brunswick Steam 

 Electric Plant, 1979-2009 and the annual mean density of total larval 

 organisms collected during larval fish sampling in the 

 Cape Fear Estuary, 1979-1993. ............................................................................ 2-22 
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List of Appendices

Appendix Page 

1 Summary of historical environmental studies conducted in association 

 with the Brunswick Steam Electric Plant, 1968-2009 .......................................... A-1 

2 Number of larval organisms collected during entrainment and larval 

 impingement sampling at the Brunswick Steam Electric Plant during 2009 ....... A-3 

3 Number and biomass of juvenile and adult organisms collected during 

 impingement sampling at the Brunswick Steam Electric Plant during 2009 ....... A-6 
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Metric-English Conversion and Units of Measure 

Length

1 micron (μm) = 4.0 x 10-5 inch 

1 millimeter (mm) = 0.001 m = 0.04 inch 

1 centimeter (cm) = 10 mm = 0.4 inch 

1 meter (m) = 100 cm = 3.28 feet 

1 kilometer (km) = 1000 m = 0.62 mile 

Volume

1 milliliter (ml) = 0.034 fluid ounce 

1 liter = 1000 ml = 0.26 gallon 

1 cubic meter = 35.3 cubic feet 

1 cubic foot per sec. = 448.8 gallons per min. 

Area 

1 square meter (m2

) = 10.76 square feet 

1 hectare (ha) = 10,000 m2

 = 2.47 acres 

Temperature

Degrees Celsius (°C) = 5/9 (°F-32) 

Weight

1 microgram (μg) = 10-3 mg or 

 10-6 g = 3.5 x 10-8 ounce 

1 milligram (mg) = 3.5 x 10-5 ounce 

1 gram (g) = 1000 mg = 0.035 ounce 

1 kilogram (kg) = 1000 g = 2.2 pounds 

1 metric ton = 1000 kg = 1.1 tons 

1 kg/hectare = 0.89 pound/acre 

 

Common and Scientific Names of Species Used in this Report

Atlantic sharpnose shark Rhizoprionodon terraenovae Gobies Gobionellus spp.

Smooth butterfly ray Gymnura micrura Gobies Gobiosoma spp.

Atlantic stingray Dasyatis sabina Atlantic cutlassfish Trichiurus lepturus

Atlantic menhaden Brevoortia tyrannus Harvestfish Peprilus alepidotus

Anchovies Anchoa spp. Flounder Paralichthys spp. 

Bay anchovy A. mitchilli Southern flounder P. lethostigma.

Striped anchovy A. hepsetus Blackcheek tonguefish Symphurus plagiusa

 Shrimp Litopenaeus & 

Farfantepenaeus spp. 

Silversides Atherinidae Brown shrimp F. aztecus

Searobin Prionotus spp. Pink shrimp F. duorarum 

Pinfish Lagodon rhomboides White shrimp L. setiferus

Star drum Stellifer lanceolatus Hardback shrimp Trachypenaeus spp. 

Silver perch Bairdiella chrysura Grass shrimp Palaemonetes spp. 

Weakfish Cynoscion regalis Swimming crab larvae Portunid megalops 

Spot Leiostomus xanthurus Blue crabs Callinectes spp. 

Croaker Micropogonias undulatus Blue crab C. sapidus

Striped mullet Mugil cephalus Lesser blue crab C. similis

Combtooth blennies Blennidae Brown bar crab Portunus spp. 

 

 
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Executive Summary

 Biological monitoring of the Cape Fear Estuary (CFE) at Progress Energy Carolinas, Inc. 

(PEC) Brunswick Steam Electric Plant (BSEP) was conducted in 2009 as part of the National 

Pollutant Discharge Elimination System (NPDES) permit requirements. Entrainment and 

impingement studies monitored the effectiveness of the intake modifications in reducing 

entrainment and impingement of fish and shellfish. 

 The fish diversion structure excluded most large organisms and many of the impinged 

larval, juvenile, and adult organisms were successfully returned alive to the estuary by using 

fine-mesh traveling screens and the fish return system. Evidence for this success includes 

species composition and abundance of organisms entrained and impinged. Anchovies, gobies, 

spot, croaker, pinfish, shrimp and crabs were the dominant larvae entrained and impinged. Use of 

fine-mesh screens has decreased the risk of entrainment for spot, croaker, pinfish, shrimp and 

crabs. These organisms potentially may be at greater risk of being entrained since they are 

spawned offshore and must pass by the plant intake in order to reach the nursery areas in the 

CFE. Anchovies and gobies on the other hand are at reduced risk because these species are 

estuarine residents and spawning occurs throughout the entire estuary. Overall reductions in the 

annual number entrained due to a combination of fine-mesh screens, the fish return system, and 

reduced cooling water flow have ranged from 57% to 87% since 1983. Based on survival 

estimates data, approximately 57% of the larval species historically tested for survival were 

returned alive to the estuary. Larval survival was greatest (> 90%) for the shrimp and crab 

larvae, the most valuable commercial taxa. 

The fish diversion structure and fish return system, when considered together, substantially 

reduced the impingement mortality of larger organisms due to cooling water withdrawal. The 

fish diversion structure excluded many of the larger fish and shellfish from the canal. Those that 

did get in and subsequently became impinged were returned alive to the CFE by the fish return 

system. Installation of the fish diversion structure significantly reduced the number of larger 

organisms impinged by as much as 99%, depending upon species. In addition to a reduction in 

numbers, a shift to the impingement of smaller finfish has resulted as well. This is important 

because the larger individuals that are not impinged are the reproducing members of the 

population. The species composition of organisms collected with impingement samples also 

shifted to a greater percentage of shrimp and blue crab rather than larger finfish as a result of the 

fish diversion structure. This is significant because these species exhibit excellent survival in the 

fish return system (> 90%). 

 Despite some variability in entrainment rates due to environmental and plant operating 

conditions there has been no evidence of long-term environmental impact. Prior to the 

installation of fine-mesh screens and the fish return system, data from intensive sampling 

throughout the 1970s indicated that operation of the plant had no measurable adverse effect on 

fish and shellfish populations in the CFE. More recent fish and shellfish population studies 

conducted during 1999, 2001 and 2002 indicated no declines in abundance of any species or 

shifts in species composition. 
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1.0 INTRODUCTION

Progress Energy Carolinas, Inc. (PEC), formerly doing business as Carolina Power & 

Light Company (CP&L), was issued an NPDES permit in December 1974. The permit allowed 

for once-through cooling water, withdrawn from the CFE, to be discharged into the Atlantic 

Ocean (Figure 1.1). A stipulation of the NPDES permit required biological monitoring to 

provide sufficient information for a continuing assessment of power plant impacts on the marine 

and estuarine fisheries of the CFE. Data were reported annually and provide an assessment of 

the effectiveness of the fish diversion structure, fine-mesh screens, and seasonally based flow 

minimization in reducing the entrainment and impingement of organisms. Organisms small 

enough to pass through the 9.4 mm mesh traveling screens may be entrained through the cooling 

water system. Larger organisms retained on the traveling screens are impinged. 

A stipulation of the renewed NPDES permit, issued in 1981, and subsequent permits was 

the implementation of power plant modifications to reduce entrainment and impingement of 

estuarine organisms resulting from the intake of cooling water. A permanent fish diversion 

structure was constructed across the mouth of the intake canal in November 1982 to reduce 

impingement by preventing larger fish and shellfish from entering the intake canal (Figure 1.2). 

In addition, the fish diversion structure significantly reduced the numbers of threatened and 

endangered sea turtles entering the intake canal. To reduce the entrainment of larvae, 1-mm 

fine-mesh screens were installed on two of the four intake traveling-screen assemblies of each 

unit in July 1983 and on a third assembly per unit in April 1987. At that time, the NPDES permit 

required that three of the four intake traveling-screen assemblies on each unit be covered with 

fine-mesh screens. In August 2003, the NPDES permit required two full fine-mesh screens 

along with two 50% fine-mesh screens on the four intake traveling screens per unit. Organisms 

retained on either the fine mesh or coarse mesh traveling screen panels are gently washed into a 

fiberglass fish return system and are subsequently returned alive to the CFE (Figure 1.2). 

Under the current permit, a maximum intake flow of 26.1 cubic meters per second (cms) 

per unit is allowed from December through March and 31.1 cms per unit is allowed from April 

through November. Normally two full fine-mesh screens and one 50% fine mesh screen are used 

during these periods of maximum intake flow. The flow of one unit may be increased to 

34.8 cms during July, August, and September. Seasonal flow minimization during December 

through March is a measure, in addition to fine-mesh screens, to reduce operational impacts on 

the large numbers of commercial finfish larvae recruiting to the estuarine nursery areas during 

that time of year. 

Environmental studies associated with the BSEP began in 1968 before the plant began 

withdrawing cooling water from the estuary. Intensive physical, chemical, and biological studies 

of the estuary and near-shore ocean were conducted in the mid and late 1970s. These original 

studies were followed by a long-term monitoring program through the early 1990s aimed at 

monitoring fish and shellfish populations within the estuary and documenting the effectiveness 

of the intake modifications at reducing the entrainment and impingement of organisms. A 

detailed summary of historic environmental studies can be found in Appendix 1. 

Intensive assessments throughout the 1970s, before the installation of fine-mesh screens 

and the fish return system, indicated that cooling-water withdrawal had no measurable adverse 
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effect on fish and shellfish populations in the Cape Fear Estuary. Annual population levels in the 

Cape Fear Estuary were determined by temperature, freshwater flow, and salinity. 

Beginning in 1994, PEC reduced the biological monitoring program with the concurrence 

of the North Carolina Department of Environment & Natural Resources. Based on almost two 

decades of operation with no detectable adverse impact on fish and shellfish populations in the 

CFE, the monitoring program was modified to concentrate on the impingement and entrainment 

of organisms (Figure 1.2). Fish population special studies conducted in the estuarine nursery 

areas during 1999, 2001 and 2002 indicated no declines in abundance of any compared to longterm data collected from the 1980s through 1993 even for bay anchovy, a species exhibiting poor 

survival in the fish return system. This report presents data for 2009 on impingement and 

entrainment rates of larval, juvenile, and adult fish and shellfish and evaluates the effectiveness 

of the NPDES-required intake modifications. 

 
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Atlantic Ocean

Ocean 

Discharge 

Area

Dutchman Creek

Plant Site

Walden 

Creek

Cape Fear River

Intake 

Canal

Southport

Visitors 

Center

NORTH 

CAROLINA

Brunswick 

Steam Electric 

Plant

N

Kilometers

Miles

0 2 4

0 2

Fish- return flume

Discharge weir *

Fish-diversion 

structure

*

Figure 1.1 Location of the Brunswick Steam Electric Plant near Southport, North 

Carolina.

 
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Intake structure

Fish return flume

Intake canal

Nancy's Creek Gum Log Branch Access road

Fish

diversion 

structure

Walden Creek

Cape Fear River

Return basin

N

0

0 1000 2000 3000

500 1000

meters 

feet 

Plant area

Discharge

Weir

Larval Impingement Sampling

Fish Return Flume

Impingement Sampling

Fish Return Flume

Entrainment Sampling

Discharge Weir

Figure 1.2 Location of fish diversion structure, fish return flume, return basin, and 

sampling locations at the Brunswick Steam Electric Plant during 2009. 
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2.0 MONITORING PROGRAM RESULTS

2.1 Introduction

Past data indicated that the impingement of large fish and shellfish of the CFE was reduced 

as a result of the 9.4-mm (3/8-inch) mesh screening on the fish diversion structure (CP&L 1984, 

1985a, 1985b). Organisms small enough to enter the intake canal through the fish diversion 

structure may be impinged on the plant intake screens and returned to the CFE via a fish return 

flume or they may be entrained through the plant. Similarly, previous studies have documented 

a reduction in the entrainment of small organisms due to the installation of fine-mesh screens at 

the intake structure and the subsequent survival of a percentage of impinged larvae returned to 

the CFE via the fish return flume (Hogarth and Nichols 1981; CP&L 1989; PEC 2008, 2009). 

Entrainment sampling during 2009 documented the species composition, seasonality, and 

abundances of larval and postlarval organisms passing through the cooling system. The larval 

impingement study evaluated the success of the fine-mesh screens in reducing entrainment of 

these organisms. Juvenile and adult (J/A) impingement sampling documented species 

composition, densities, weights, and lengths of juvenile and adult organisms impinged during 

2009 and provided evidence of the continued effectiveness of the fish diversion structure. Note 

that the J/A impingement study addressed the impingement of organisms that would typically be 

impinged on conventional 9.4-mm (3/8-inch) mesh traveling screens. Survival study results 

from previous years were used to estimate the effectiveness of the return system for returning 

impinged organisms alive to the CFE (CP&L 1987, 1988). 

2.2 Methods

Intake canal water temperature and salinity measurements were collected from the fish return 

flume during impingement sampling. Daily freshwater flow values presented in the report were 

downloaded from the United States Geological Survey website. Total freshwater input to the 

CFE was estimated using data from stream gaging stations in the Cape Fear, Northeast Cape 

Fear, and Black Rivers according to the methods presented by Giese et al. (1979, 1985). 

The collection gear used for entrainment and impingement sampling has remained 

unchanged since 1984 (CP&L 1985a). Entrainment sampling was conducted in the discharge 

weir (Figure 1.2). Larval impingement and J/A impingement sampling were conducted in the 

fish return flume. The J/A impingement program included fish and shrimp ≥ 41 mm, portunid 

crabs ≥ 25 mm, and eels and pipefish ≥ 101 mm. Impinged organisms smaller than these size 

limits would have been entrained without use of fine-mesh screens and were analyzed with the 

larval impingement sampling program. 

Densities calculated for all larval organisms were averaged to obtain a mean number per 

1,000 m3

 of water entrained through the plant per sampling date. Densities for J/A organisms 

impinged on each sampling date were calculated by dividing the total number of organisms 

collected by the volume of water pumped through the plant. Densities were expressed as the 

number per million cubic meters of water pumped through the plant during each 24-hour 

sampling period. 
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For both entrainment and larval impingement sampling, rates and densities of total number 

of organisms and selected taxa collected were expanded to give an estimate for 24 hours. 

Entrainment and larval impingement rates per 24-hour sampling period during 2008 were 

summed to find the total number of larvae affected. The percent effectiveness (how successfully 

the organisms were kept from being entrained) of fine-mesh screens was calculated as the ratio 

between the larval impingement rate and the total number (entrainment plus larval impingement) 

affected for each sampling trip. 

An overall assessment of reductions in entrainment due to fine-mesh screens, fish return 

system, and NPDES permit limitations on plant cooling-water flow was conducted using 

historical entrainment data collected from 1979 through 2009. However, data collected in 1983 

were excluded from the analysis since fine-mesh screens and the fish return system were not 

fully operational for a portion of that year. Both of these intake modifications were completed 

during June 1983. Data prior to 1983 can be used to estimate annual numbers entrained during a 

period with no controls in place (i.e., no fine-mesh screens, fish return system, or NPDES permit 

limitations of flow). Mean daily entrainment densities were multiplied by design cooling water 

flow and summed to obtain an annual estimate of total number entrained. Design flow is the 

rated flow of all main cooling water pumps per unit plus service water and screen wash flows. 

The summation of these flows result in a total design flow of 84.15 cms. Details and rated pump 

capacities can be found in the Proposal for Information Collection compiled as required by the 

Phase II 316(b) rule (PEC 2005). Linear interpolation was used to estimate entrainment rates on 

non-sampling days. Annual numbers entrained after 1983 were calculated in a similar fashion 

with the exception that actual cooling-water flow was used. A calculated annual baseline 

entrainment rate was obtained by averaging the annual number entrained for the years 1979 

through 1982. The estimated annual number entrained each year after 1983 was subtracted from 

the annual baseline estimate to obtain a percentage reduction from baseline due to the installation 

of fine-mesh screens, fish return system, and reduced cooling-water flow. Additional insight 

was obtained by comparing annual entrainment estimates to the mean annual density of larvae 

entering the estuary from 1979 through 1993. 

 Survival in the return system was determined for selected size classes of the dominant 

organisms that have been impinged at the BSEP in past years (CP&L 1985a, 1986, 1987, 1988). 

Survival estimates were calculated using survival rates determined during previous studies for 

fast-screen rotation (CP&L 1987, 1988). 

2.3 Results and Discussion 

2.3.1 Water Quality 

•Intake canal salinity ranged from a low of 14 ppt during December to a high of 29 ppt 

during November (Figure 2.1). Freshwater input varied during 2009 with peak flows 

occurring during March, November, and December. Except for 2006, the annual 

mean freshwater input to the CFE remained relatively low flows for the period 2005-

2009 when compared to the long-term annual mean flow of 269 cms for the period 

1980-2004 (Figure 2.2). 
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•Intake canal water temperature ranged from 8.5°C during March to a high of 29.9°C 

during August (Figure 2.3). Mean water temperature during the peak recruitment 

season for most winter spawners (January-March) was relatively cool during 2009, 

compared to temperatures for the previous three years (Figure 2.4). Little difference 

was evident for mean summer water temperature (June-August) among these years. 

2.3.2 Dominant Species 

•Anchovies, spot, and Gobiosoma spp. were the most abundant taxa collected in 

entrainment samples during 2009 (Table 2.1). Croaker, shrimp (larval Penaeidae), 

silversides, portunid crab megalops, Blennidae, and Atlantic menhaden were also 

among the ten most numerous taxa entrained entrained during 2009. A complete 

species list showing numbers collected can be found in Appendix 2. The annual 

mean density of total organisms collected in entrainment samples during 2009 was 

approximately 30% less than the annual mean density of total organisms collected 

during 2008. 

•Ten taxa accounted for 86% of the total larval organisms collected in larval 

impingement samples during 2009 (Table 2.2). The most dominant larvae impinged 

on the fine-mesh screens were shrimp, spot, croaker, and Anchoa spp. (≥ 13 mm). 

Hardback shrimp, portunid crab megalops, Gobiosoma spp., Anchoa spp. (< 13 mm), 

swimming crabs (juvenile Portunidae), and Atlantic menhaden were also among the 

top ten larval taxa impinged during 2009. Although the relative ranking has varied, 

the same ten most abundant species have generally dominated larval impingement 

samples each year since 1984. A complete species list showing numbers collected 

can be found in Appendix 2. 

•Commercially and recreationally important taxa dominated larval impingement samples 

indicating that use of fine-mesh screens successfully reduced the entrainment of these 

important taxa. The number of taxa collected in larval impingement samples by 

month was generally greater than the number collected in entrainment samples 

during 2009 due to the use of fine-mesh screens (Figure 2.5). This relationship is 

important because it indicates that use of fine-mesh screens reduces the risk of 

entrainment for the larvae found in the CFE. 

• During 2009, J/A impingement samples were numerically dominated by bay anchovy, 

white shrimp, and spot (Table 2.3). Brown shrimp, croaker, blackcheek tonguefish, 

Atlantic menhaden, threadfin shad, blue crab and rough silverside were also among 

the top ten species collected during 2009. These top ten species accounted for 93% 

of the number collected and approximately 85% of the biomass collected during 

2009. Prior to intake modifications in 1983, Atlantic menhaden and larger finfish, 

such as spot and croaker, dominated both the number and biomass collected with J/A 

impingement sampling (CP&L 1980a, 1980b, 1982, 1983). This shift in species 

composition was a result of the exclusion of larger finfish by the fish diversion 

structure and is significant because impingement samples have become dominated by 

shrimp and crabs. Both shrimp and crabs exhibit relatively high survival in the fish 

return system. Additional species that contributed to the biomass impinged include 
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smooth butterfly ray (6.0 kg), fringed flounder (3.4 kg), and lesser blue crab (3.1 kg). 

A complete species list showing numbers and weights collected can be found in 

Appendix 3. 

•No rare, threatened or endangered species were collected with entrainment or 

impingement sampling during 2009. 

2.3.3 Seasonality and Abundance

•Seasonal variations for larvae entrained and impinged in 2009 were similar to seasonal 

variations observed in previous years and corresponded to the seasonality of larval 

fish in the CFE (Tables 2.4, 2.5, and 2.6; CP&L 1994). This observation is important 

since it indicates that recruitment to and within the estuary is functioning normally 

and has not been disrupted by cooling water withdrawal or other environmental 

perturbations. Minor changes in peaks of abundance in entrainment and 

impingement of organisms are normal and can be influenced by environmental 

conditions such as changing freshwater discharge to the estuary, operating fewer 

fine-mesh screens, increasing or decreasing the flow of cooling water as determined 

by plant operational needs, and sampling period (Blumberg et al. 2004; Copeland et 

al. 1979; Lawler et al. 1988; Thompson 1989). 

•The typical winter and summer periods of abundance observed during 2009 in the 

entrainment program were also observed in the larval impingement program 

(Table 2.6). Atlantic menhaden, spot, croaker, and pinfish, all ocean-spawned 

species, were most abundant during winter and early spring. Shrimp larvae were most 

abundant during spring, summer, and early fall. Estuarine-spawned species (e.g., 

anchovies, Gobiosoma spp., silversides, and Blennidae) were most abundant during 

the spring and summer. The period of abundance for portunid crab megalops 

occurred during the fall and early winter. 

•Seasonality of larger individuals collected during J/A impingement sampling were 

consistent with data collected from previous years and the natural seasonality 

reported for these species in the lower CFE by Schwartz et al. (1979). Results 

indicate that impingement of finfish was comprised mostly of young-of-year 

individuals too small to be excluded by the fish diversion structure. Impingement of 

significant numbers of larger fish has been virtually eliminated by the installation of 

the fish diversion structure. Atlantic menhaden that were abundant during January 

were yearling individuals (Table 2.7). Peak densities of spot and croaker collected 

during January through March also consisted of yearling individuals spawned the 

previous calendar year. Bay anchovy, collected year round, was most abundant 

during the winter and fall when past data indicated that most of the individuals 

comprising the population had grown to a size large enough to be impinged on the 

coarse-mesh traveling screens. Peak densities of white, brown, and pink shrimp 

occurred during the summer recruitment period. Blue crab was most abundant 

during August. 
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•The seasonality for total number of all organisms impinged (January through March, 

November, and December) was driven by the large numbers of bay anchovy 

collected (Table 2.7). Once bay anchovy is excluded, a pattern emerges where the 

greatest number impinged by month occurred during January, August, and 

November. Shrimp and blue crab were the dominant organisms impinged during 

August and November. Both taxa are characterized by high survival rates in the fish 

return system (CP&L 1987, 1988). 

•Installation of the fish diversion structure has resulted in a decline in the densities of 

most J/A organisms impinged. Species that dominated impingement prior to 

installation of the diversion structure include Atlantic menhaden, spot, croaker, and 

blue crabs. During 2009, the mean density of these species collected with J/A 

impingement sampling has been reduced by 59% for spot to a reduction of 99% for 

Atlantic menhaden in comparison to the average baseline density (Table 2.8). The 

average biomass (weight per million cubic meters of water) impinged for these 

species was reduced by approximately 65% for spot to a reduction of 99% for 

Atlantic menhaden when compared to the baseline biomass. 

2.3.4 Fine-Mesh Screens and Cooling Water Flow

•The overall effectiveness of fine-mesh screens in reducing entrainment for total 

organisms ranged from 2% in May to 44% in April (Table 2.9). The variability of 

their effectiveness in reducing entrainment was influenced by the number of finemesh screens operating, species composition, seasonality, and organism size. Species 

body size and shape have been shown to have an effect on screening efficiency for 

other species of larval fish (Tomljanovich et al. 1978; Stone & Webster Engineering 

Corporation 1984). 

• By taxon, the overall annual effectiveness ranged from < 1% for combtooth blenny to 

87% for juvenile blue crabs (swimming crabs), a valuable commercial species. 

During March when fine-mesh screen efficiencies were highest, the dominant larvae 

were larger anchovies (Anchoa spp. ≥ 13 mm), spot, pinfish, croaker, Atlantic 

menhaden and shrimp (Tables 2.4, 2.5, 2.6, and 2.9). The lowest fine-mesh screen 

efficiencies for the year were recorded during May when non-commercially 

important taxa such as goby (Gobiosoma spp.), silversides, and smaller anchovy 

larvae (Anchoa spp. < 13 mm) were numerically dominant (these taxa typically 

exhibit relatively poor fine-mesh screen efficiency).

• The percentage reduction in entrainment from baseline for total organisms has ranged 

from 57% to 87% since 1983 (Figure 2.6). This meets the entrainment reduction 

thresholds (60-90%) proposed by the Phase II 316(b) rule currently in revision. 

Comparison of the annual number entrained to the mean annual larval density from 

1979 through 1993 indicated that the reductions in entrainment were due to the 

installation of the fine-mesh traveling screens and the fish return system plus reduced 

cooling water flow and not due to any declines in the abundance of larvae in the CFE 

(Figure 2.7). Although there was normal inter-annual variability in the density of 

larvae collected from the CFE through 1993 there was no decreasing trend in density.
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Progress Energy Service Company, LLC 2-6 Environmental Services Section

2.3.5 Survival Estimates

•Fourteen of the most commonly impinged larval taxa were previously tested for 

survival on fast-screen rotation speed (Table 2.10). These fourteen taxa accounted 

for approximately 91% of the total larval impingement catch. Survival during fastscreen rotation ranged from approximately 1% for anchovies (Anchoa spp. ≥ 13 mm) 

to approximately 96% for pink and white shrimp. 

•Approximately 57% of the selected larval organisms were returned alive to the estuary. 

•Eleven taxa of the dominant J/A organisms impinged were previously tested for 

survival during fast-screen rotation (Table 2.11; CP&L 1987, 1988). In addition, 

survival of star drum and silver perch was estimated using data for two closely 

related species (croaker and spot). These thirteen taxa accounted for approximately 

93% of the total number collected and 87% of the total weight collected. 

•Excluding bay anchovy, survival ranged from 16% for Atlantic menhaden to 96% for 

blue crabs. The most valuable commercial species (shrimp and blue crabs) exhibited 

the highest survival rates. Survival estimates indicated that 76% of the total number 

and 72% of the total biomass of organisms impinged, excluding bay anchovy, were 

returned alive to the estuary during 2009. 

2.4 Summary and Conclusions

There has been no evidence of long-term environmental impact despite some variability in 

entrainment rates due to environmental and plant operating conditions. The seasonality of 

organisms collected in the entrainment, larval impingement, and J/A impingement studies during 

2009 were similar to previous years and corresponded to the natural seasonality of larval 

organisms in the Cape Fear Estuary. The Brunswick Steam Electric Plant intake modifications 

and operational measures continued to be effective in reducing the number of organisms affected 

by the withdrawal of cooling water from the Cape Fear Estuary. Evidence supporting this 

conclusion includes species composition and abundance of organisms entrained and impinged. 

Anchovies, gobies, spot, croaker, pinfish, shrimp and crabs were the dominant larvae entrained 

and impinged. Use of fine-mesh screens has decreased the risk of entrainment for spot, croaker, 

pinfish, shrimp and crabs. These organisms may potentially be at more risk of being entrained 

since they are spawned offshore and pass by the plant intake in order to reach the nursery areas 

in the Cape Fear Estuary. Conversely, anchovies and gobies are at less risk since they are 

estuarine residents and spawning occurs throughout the entire estuary. Overall, use of fine-mesh 

screens reduced the numbers of all organisms entrained by up to approximately 44% during 

2009. The greatest reductions in entrainment due to fine-mesh were evident for shrimp and crab 

larvae, the most valuable commercial species. Larvae that would have been entrained were 

returned alive by the fish return system to the CFE in significant numbers. Overall reductions in 

the annual number entrained due to a combination of fine-mesh screens, the fish return system, 

and reduced cooling water flow ranged from 57% to 87% since 1983. Based on survival 

estimates data, approximately 57% of the larvae tested for survival were returned alive to the 

estuary. The most valuable commercial taxa, shrimp and crab larvae, exhibited the greatest 

survival (> 87%). 
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Considered together, the fish diversion structure and fish return system has substantially 

reduced the impingement mortality of larger organisms due to cooling water withdrawal. The 

fish diversion structure excludes many of the larger fish and shellfish from the canal. Those that 

do get in and subsequently become impinged and substantial numbers of fish and shellfish are 

returned alive to the CFE by the fish return system. Installation of the fish diversion structure 

significantly reduced the number of larger organisms impinged at the plant. Conservative 

estimates of the effectiveness were between 57%-99% for the historically dominant species 

impinged. In addition to a reduction in numbers, a shift to the impingement of smaller finfish 

has resulted as well. This shift to smaller individuals is important because the larger individuals 

that are being excluded (saved) are the reproducing members of the population. In addition, the 

natural mortality rates (predation, weather, tides, etc.) of smaller individuals is relatively high 

compared to the natural mortality rates of older, larger individuals so many of the smaller 

individual would not survive to maturity even in the absence of Plant operation. The species 

composition of organisms collected with impingement sampling also shifted to a greater 

percentage of shrimp and blue crabs rather than larger finfish as a result of the fish diversion 

structure. This shift in species composition is significant since juvenile and adult shrimp and 

crabs exhibit excellent survival in the fish return system (> 90%). 

 
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Table 2.1 Annual mean density (no./1000 m3) and percent of total for the ten most 

abundant taxa collected during entrainment sampling at the Brunswick 

Steam Electric Plant during 2008 and 2009 (based on ranking for 2009).

 

 2008 2009 

 Annual mean Annual mean 

Taxon density Percent density Percent

 

Anchoa spp. (< 13 mm) 11.4 8.2 21.7 22.4

Spot 15.1 10.9 16.3 16.9 

Gobiosoma spp. 22.7 16.4 15.3 15.8 

Anchoa spp. (> 13 mm) 28.8 20.8 13.7 14.2 

Croaker 14.8 10.7 7.9 8.3

Shrimp 8.0 5.8 5.5 5.7 

Silversides 1.4 1.0 5.0 5.2 

Portunid crab megalops 2.5 1.8 2.1 2.1 

Blennidae 1.5 1.1 1.5 1.6 

Atlantic menhaden 3.2 2.3 1.4 1.4 

Other taxa (n = 44 for 2008) 29.3 21.2 6.3 6.5 

 (n = 42 for 2009) 

 

Total organisms+

 138.7 100.0 96.7 100.0 

 

+ Total may vary from summation due to rounding of individual taxon. 
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Table 2.2 Total number of the ten most abundant taxa estimated for larval 

impingement sampling at the Brunswick Steam Electric Plant during 2008 

and 2009 (based on ranking for 2009). 

 

 2008 2009 

Taxon Total number+

 Percent Total number+ Percent 

 

Shrimp 3.0 x 106

 24.4 3.5 x 106 28.4 

Spot 1.8 x 106 14.3 1.6 x 106 12.8 

Croaker 2.3 x 106

 19.0 1.4 x 106 11.7

Anchoa spp. (≥13 mm) 2.3 x 106

 18.9 1.6 x 106 11.0 

Hardback shrimp 1.4 x 105 1.2 8.4 x 105 6.8

Portunid megalops 4.6 x 105

 3.8 6.4 x 105 5.2

Gobiosoma spp. 6.5 x 104 0.5 4.3 x 105 3.5 

Anchoa spp. (<13 mm) 5.6 x 104 0.5 2.9 x 105 2.4

Swimming crabs 6.0 x 104 0.5 2.1 x 105 1.7 

Atlantic menhaden 4.0 x 105 3.3 9.9 x 104 0.8

Other taxa (n = 51 for 2008) 1.7 x 106 13.7 5.1 x 105 4.7 

 (n = 56 for 2009) 

 

Total& 12.2 x 106

 100.0 10.8 x 106 100.0 

+

Total number is a sum of the twelve sampling-day totals. 

&

Total may vary from summation due to rounding of individual taxon. 
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Table 2.3 Total number, total weight, and percent of total of the ten most abundant 

juvenile and adult organisms collected in the Brunswick Steam Electric Plant 

impingement samples during 2009.

 

Taxon Number+

 Percent& Weight (kg)+ Percent&

 

Bay anchovy 73,328 64.6 77.1 19.2

White shrimp 11,778 10.3 79.8 19.9

Spot 8,776 7.7 74.5 18.6 

Brown Shrimp 3,172 2.8 21.2 5.3

Croaker 2,120 1.9 32.1 8.0 

Blackcheek toungefish 2,098 1.8 9.1 2.3 

Atlantic menhaden 1,949 1.3 20.7 5.1 

Threadfin shad 1,154 1.0 4.9 1.2

Blue crab 1,037 0.9 21.8 5.4

Rough silverside 1,027 0.9 1.8 0.4 

Other taxa (n = 77 for 2009) 7,520 6.8 58.2 14.6 

 

Total 113,959 100.0 401.2 100.0

 

+

Numbers and weights are sums of the twelve sampling day totals. 

&

Percentages may not add up to 100 due to rounding. 
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Table 2.4 Entrainment densities (mean no./1000 m3 per sampling day) of selected taxa+

at the Brunswick Steam Electric Plant during 2009. 

Month

Taxa Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

 

Anchoa spp. 

(< 13 mm) 0 0 0 0 1,773 198 46 157 34 0 0 0

 

Anchoa spp. 

(> 13 mm) 

20 58 31 2 168 601 225 55 15 21 79 127

 

Spot 392 629 596 47 0 0 0 0 0 0 0 3

Pinfish 20 24 20 0 0 0 0 0 0 0 0 0

 

Croaker 247 66 58 25 0 0 0 0 0 78 101 240

Atlantic menhaden 7 57 58 11 0 0 0 0 0 0 0 6

Silversides 0 0 0 242 269 0 0 0 0 0 0 0

 

Gobiosoma spp. 0 0 0 0 657 557 208 59 38 33 0 0

 

Combtooth 

blennies 0 0 0 0 80 27 35 6 6 0 0 0

Microgobius spp. 0 0 0 2 3 68 15 9 7 0 0 0

 

Shrimp 33 10 21 122 0 169 61 13 28 59 34 10

Hardback shrimp 0 0 0 0 0 0 15 0 33 0 0 3

Swimming crabs 0 0 0 0 0 0 0 2 0 6 0 0

Portunid crab 

megalops 0 0 0 0 11 3 0 0 5 131 33 34

 

Total organisms 731 894 834 482 3,092 1,681 611 317 172 333 280 435

+

Selected taxa comprised ≥ 1% of the total sampled in either entrainment or larval impingement 

sampling.
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Table 2.5 Entrainment rates (million per sampling day) of selected taxa+ at the 

Brunswick Steam Electric Plant during 2009. 

Month

Taxa Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec 

 

Anchoa spp. 

(< 13 mm) 

0 0 0 0 9.370 1.045 0.253 0.859 0.184 0 0 0 

 

Anchoa spp. 

(> 13 mm) 

0.088 0.262 0.070 0.008 0.890 3.178 1.229 0.299 0.081 0.112 0.416 0.574

 

Spot 1.771 2.838 1.344 0.211 0 0 0 0 0 0 0 0.015

Pinfish 0.090 0.109 0.045 0 0 0 0 0 0 0 0 0

 

Croaker 1.114 0.300 0.130 0.113 0 0 0 0 0 0.412 0.533 1.085

Atlantic menhaden 0.030 0.256 0.131 0.049 0 0 0 0 0 0 0 0.029

Silversides 0 0 0 1.084 1.420 0 0 0 0 0 0 0 

Gobiosoma spp. 0 0 0 0 3.470 2.994 1.136 0.323 0.208 0.176 0 0 

Combtooth 

blennies 0 0 0 0 0.422 0.141 0.192 0.034 0.034 0 0 0 

Microgobius spp. 0 0 0 0 0.018 0.360 0.079 0.050 0.036 0 0 0 

 

Shrimp 0.147 0.047 0.047 0.548 0 0.894 0.332 0.069 0.151 0.310 0.177 0.045

Hardback shrimp 0 0 0 0 0 0 0.080 0 0.180 0 0 0.015

Swimming crabs 0 0 0 0 0 0 0 0 0.033 0 0 0 

Portunid crab 

megalops 0 0 0 0 0.060 0.015 0 0 0.025 0.694 0.177 0.153

 

Total organisms 3.298 4.034 1.882 2.159 16.342 8.882 3.332 1.728 0.940 1.762 1.478 1.961

+

Selected taxa comprised ≥ 1% of the total sampled in either entrainment or larval impingement 

sampling. 
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Table 2.6 Estimated total number (million per sampling day) of selected taxa+ collected 

with monthly larval impingement sampling at the Brunswick Steam Electric 

Plant during 2009. 

Month

Taxa Jan Feb Mar Apr May Jun Jul Aug Sept Oct Nov Dec 

 

Anchoa spp. 

(< 13 mm) 

0 0 0 0.006 0.089 0.042 0.057 0.105 0.001 0 0 0 

 

Anchoa spp. 

(> 13 mm) 

0.085 0.014 0.023 0.016 0.110 0.107 0.494 0.110 0.081 0.006 0.162 0.144 

 

Spot 0.309 0.501 0.518 0.227 0 0 0 0 0 0 0 0.008 

 

Pinfish 0.010 0.032 0.032 0.007 0 0 0 0 0 0 0 0.002 

 

Croaker 0.230 0.141 0.136 0.055 0.001 0 0 0.001 0 0.008 0.105 0.756

 

Atlantic menhaden 0.008 0.033 0.056 0 0 0 0 0 0 0 0 0.002 

 

Silversides 0 0 0 0.011 0.002 0 0 0.002 0 0 0 0

 

Gobiosoma spp. 0 0 0 0 0.014 0.320 0.021 0.059 0.004 0.005 0.002 0

 

Combtooth 

blennies 

0 0 0 0 0.001 0 0 0 0 0 0 0

 

Microgobius spp. 0 0 0 0 0 0.015 0.005 0 0 0 0 0

 

Shrimp 0.068 0 0.001 1.249 0.096 1.152 0.273 0.057 0.191 0.080 0.193 0.025

 

Hardback shrimp 0 0 0 0 0 0.109 0.159 0.066 0.426 0.014 0.061 < 0.001

 

Swimming crabs 0 0 0 0.003 0.003 0.108 0.002 0.016 0.024 0.044 0.012 0.001

 

Portunid crab 

megalops 0.002 0 0.001 0.008 0.018 0.031 0.018 0.021 0.083 0.125 0.285 0.043

 

Total organisms 0.725 0.791 0.877 1.668 0.403 1.931 1.039 0.464 0.818 0.293 0.839 0.998

+

Selected taxa comprised > 1% of the total sampled in either entrainment or larval impingement 

sampling.
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Table 2.7 Density (no./million m3 of water entrained during each 24-hour sampling 

period) and modal length for selected species+ collected with juvenile and adult 

impingement sampling per month at the Brunswick Steam Electric Plant 

during 2009. 

Month

Taxa Jan Feb Mar Apr May Jun Jul Aug Sept Oct Nov Dec 

 

Bay anchovy& 

density 3,963 1,205 6,204 675 450 101 18 35 18 1 1,841 4,339

 

Atlantic 

menhaden 

density 288 13 7 3 14 1 2 0 < 1 0 0 0

modal length 85 100 95 95 115 IN§ IN IN IN

 

 

Spot 

density 1,396 291 382 6 15 3 0 2 2 0 0 0

modal length 75 75 75 80, 85 45 110 IN IN

 

Croaker 

density 338 18 32 90 2 0 1 0 0 1 0 0

modal length 100 110 110 60 IN IN IN 

 

White shrimp 

density 1,106 20 6 2 3 0 1 307 100 78 512 290

modal length 105 90 135 IN 120 IN 95 120 110 75 85

 

Brown shrimp 

density 0 0 0 0 35 204 282 62 5 0 0 0

modal length 50 85 105 90 70 

 

Pink shrimp 

density 5 2 0 1 7 0 0 112 13 3 14 25

modal length IN IN IN IN 45, 55 65 50, 55 70 50

 

Blue crab& 

density 57 23 9 37 24 21 22 96 45 15 17 33

 

Total organisms 3,190 367 436 139 100 229 308 579 166 97 543 348

excluding bay anchovy 

 

Total organisms 7,153 1,572 6,640 814 550 330 326 614 184 98 2,384 4,723

+

Selected species, with the exception of bay anchovy, are commercially and recreationally important species that 

accounted for greater than 1% of the total catch by number or weight. 

&Length-frequency analysis was not conducted on bay anchovy or blue crab data. 

§

IN= insufficient number collected for length-frequency analysis 
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Table 2.8 Mean density and biomass of selected juvenile and adult organisms indicating 

reductions in density and biomass impinged during 2009 as a result of the fish 

diversion structure. 

Density (number/million m3) + Biomass (kg/million m3) +

Taxa Pre-diversion& 2009 

Percent 

reduction Pre-diversion& 2009 

Percent 

reduction

 

Atlantic menhaden 5,481 26 99.5 38.8 0.4 99.9 

 

Spot 362 150 58.6 3.7 1.3 64.9 

 

Croaker 199 36 81.9 5.7 0.6 89.5 

 

Blue crabs 351 34 90.3 4.5 0.4 90.4 

 

+

Density and biomass are expressed as number and weight (kg) of organisms impinged per 

million m3 of water pumped by the plant. 

&

Density values are means of all years (1977-1981) prior to completion of the diversion 

structure. 
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Table 2.9 Percent effectiveness+ of fine-mesh screens in reducing the number entrained 

per day for selected taxa at the Brunswick Steam Electric Plant during 2009. 

 Month 

Taxa Jan Feb Mar Apr May Jun Jul Aug Sept Oct Nov Dec Annual

 

Anchoa spp. 

(< 13 mm) NP& NP NP 100 1 4 18 11 1 NP NP NP 2 

 

Anchoa spp. 

(> 13 mm) 49 5 25 67 11 3 29 27 50 5 28 20 16 

 

Spot 15 15 28 52 NP NP NP NP NP NP NP 35 20 

 

Pinfish 10 23 42 100 NP NP NP NP NP NP NP 100 25 

 

Croaker 17 32 51 33 100 NP NP 100 NP 2 16 41 28 

 

Atlantic 

menhaden 21 11 30 0 NP NP NP NP NP NP NP 6 17 

 

Silversides NP NP NP 1 1 NP NP 100 NP NP NP NP 1 

 

Gobiosoma spp. NP NP NP NP 0 10 2 15 2 3 100 NP 5 

 

Combtooth 

blenny NP NP NP NP 0.2 0 0 0 0 NP NP NP 0.1 

 

Microgobius spp. NP NP NP NP 0 4 6 0 0 NP NP NP 4 

Shrimp 32 0 2 70 100 56 45 45 56 21 52 36 55 

 

Hardback shrimp NP NP NP NP NP 100 67 100 70 100 100 1 75 

Swimming crabs NP NP NP 100 100 100 100 100 42 100 100 100 87 

 

Portunid crab 

megalops 100 NP 100 100 23 67 100 100 77 15 62 22 36 

 

Total 

Organisms 18 16 32 44 2 18 24 21 47 14 36 34 21 

+

Percent effectiveness = [no. collected in larval impingement samples/( no. collected in larval 

impingement samples + no. collected in entrainment samples)] x 100 

&

NP = Not Present. 
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Table 2.10 Estimated numbers and percent survival of selected larval organisms 

collected during fine-mesh screen sampling (larval impingement) at the 

Brunswick Steam Electric Plant during 2009. 

 Total Percent+ Number&

Taxa number survival survived 

 

Shrimp 3,480,048 90.3 3,142,483 

Croaker 1,433,232 33.7 482,999 

Anchoa spp. > 13 1,351,728 0.7 9,462 

Spot 1,562,544 29.4 459,388 

Portunid Megalops 636,336 87.0 553,612 

Atlantic menhaden 99,216 3.2 3,175 

Hardback shrimp 835,632 78.8 658,478 

Gobionellus spp. 67,392 15.4 10,378 

Blue crabs 243,072 91.7 222,897 

Flounder spp. 22,896 93.2 21,339 

Pink and white shrimp 4,608 95.8 4,414 

Weakfish 11,088 12.6 1,397 

Mullet 70,416 69.8 49,150 

Prionotus spp. 5,616 89.8 5,043 

 

 

Total selected taxa 9,823,824 57.3 5, 624,217 

 

+

Reference: CP&L 1987 and 1988 (fast-screen rotation). 

 &The number survived is a total for the 12 sampling days and not the entire year. 
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Table 2.11 Estimated numbers, biomass (kg), and percent survival of selected juvenile 

and adult organisms collected during impingement sampling at the 

Brunswick Steam Electric Plant during 2009. 

 Total Total Percent Number Biomass 

Taxa number biomass survival+ survived& survived 

 

Bay anchovy 73,628 77.1 4.9 3,608 3.8 

Pink & white shrimp 12,732 81.8 93.7 11,930 76.6 

Brown shrimp 3,172 21.2 90.4 2,867 19.2 

Blue crabs 1,395 26.0 96.2 1,342 25.0 

Spot 8,776 74.5 60.4 5,301 45.0 

Blackcheek tonguefish 2,098 9.1 83.1 1,743 7.5 

Atlantic menhaden 1,494 20.7 15.6 233 3.2 

Croaker 2,120 32.1 45.1 956 14.5 

Star drum¶ 468 1.6 45.0 211 0.7 

Weakfish 60 0.3 35.0 21 0.1 

Silver perch¶ 323 2.3 60.4 195 1.4 

Striped mullet 39 0.7 92.0 36 0.6 

Flounder 39 1.3 71.1 28 0.9 

 

 

Total 106,344 348.6 28473 198.6 

 

Percent survival 26.8 56.9 

(selected taxa) 

 

Percent survival 76.0 71.7 

(selected taxa excluding bay 

anchovy) 

+

Reference: CP&L 1988 (fast-screen rotation). 

&

Number and weight collected and survived are a total for the 12 sampling days and not the 

entire year. 

¶

Survival percentages for star drum and silver perch are estimates based upon data for similar 

species (croaker, spot) 

 
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Progress Energy Service Company, LLC 2-19 Environmental Services Section

0

5

10

15

20

25

30

35

0

200

400

600

800

1,000

1,200

Salinity (ppt)

Freshwater Flow (cms)

Freshwater Flow Intake canal salinity

Figure 2.1 Mean daily freshwater flow to the Cape Fear Estuary and monthly intake 

canal salinity at the Brunswick Steam Electric Plant during 2009. 

0

100

200

300

2005 2006 2007 2008 2009

Freshwater Flow (cms)

269 cms = mean annual flow 1980-2004

Figure 2.2 Mean annual freshwater flow to the Cape Fear Estuary, 2005–2009.
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0

5

10

15

20

25

30

35

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Temperature (°C)

Figure 2.3 Mean monthly intake canal water temperature (°C) at the Brunswick Steam 

Electric Plant during 2009. 

0

5

10

15

20

25

30

2005 2006 2007 2008 2009

Temperature (°C)

Winter Summer

Figure 2.4 Mean winter and summer intake canal water temperatures (°C) at the 

Brunswick Steam Electric Plant, 2005-2009. 
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13 14

11

18

21 21 19

23

13

21

16

20

57

9 10 12

16

19 21

10

15

12 10 8 9

44

0

10

20

30

40

50

60

70

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Annual

Number of Taxa

Larval impingement

Entrainment

Figure 2.5 Number of taxa collected in entrainment and larval impingement samples at 

the Brunswick Steam Electric Plant during 2009. 

Photograph of February 2006 larval impingement sample.

These larvae would have been entrained without the use of fine-mesh screens 

(Provided for information only and is not cited in the text.) 

 
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Progress Energy Service Company, LLC 2-22 Environmental Services Section

0

20

40

60

80

100

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

1979198019811982198319841985198619871988198919901991199219931994199519961997199819992000200120022003200420052006200720082009

Percent Reduction

Number Entrained (millions)

Percent reduction

Baseline

Fine-mesh screens and return system installed 1983

Annual number entrained

Figure 2.6 Annual number of total organisms entrained at the Brunswick Steam Electric 

Plant and percent reduction from baseline entrainment estimates, 1979-2009. 

(Annual numbers entrained prior to 1983 were averaged to obtain the baseline 

entrainment estimate.) 

0

500

1000

1500

2000

2500

3000

3500

0

1000

2000

3000

4000

5000

6000

7000

8000

9000

1979198019811982198319841985198619871988198919901991199219931994199519961997199819992000200120022003200420052006200720082009

Larv al density (Nu./1000 m3)

Number Entrained (millions)

Annual number entrained

Mean Annual Larval Density

Figure 2.7 Annual number of total organisms entrained at the Brunswick Steam Electric 

Plant, 1979-2009 and the annual mean density of total larval organisms 

collected during larval fish sampling in the Cape Fear Estuary, 1979-1993 

(Estuarine larval fish sampling was discontinued after 1993) . 
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3.0 REFERENCES

Blumberg, A. F., D. J. Dunning, H. Li, D. Heimbugh, and W. R. Geyer. 2004. Use of a particle 

tracking model for predicting entrainment at power plants on the Hudson River. Estuaries. 27 

(3): 515 - 526 . 

CP&L. 1984. Brunswick Steam Electric Plant annual biological monitoring report, 1983. 

Carolina Power & Light Company, New Hill, NC. 

 .1985a. Brunswick Steam Electric Plant annual biological monitoring report, 1984. Carolina 

Power & Light Company, New Hill, NC. 

 . 1985b. Brunswick Steam Electric Plant Cape Fear Studies, Interpretive Report. Carolina 

Power & Light Company, New Hill, NC. 

 . 1986. Brunswick Steam Electric Plant annual biological monitoring report, 1985. Carolina 

Power & Light Company, New Hill, NC. 

 . 1987. Brunswick Steam Electric Plant annual biological monitoring report, 1986. Carolina 

Power & Light Company, New Hill, NC. 

 . 1988. Brunswick Steam Electric Plant annual biological monitoring report, 1987. Carolina 

Power & Light Company, New Hill, NC. 

 . 1989. Brunswick Steam Electric Plant annual biological monitoring report, 1988. Carolina 

Power & Light Company, Southport, NC. 

Copeland, B. J., R. G. Hodson, and R. J. Monroe. 1979. Larvae and postlarvae in the Cape Fear 

Estuary, North Carolina, during operation of the Brunswick Steam Electric Plant, 1974-1978. 

North Carolina State University, Raleigh, NC. 

Giese, G. L., H. B. Wilder, and G. G. Parker, Jr. 1979. Hydrology of major estuaries and sounds 

of North Carolina. United States Geological Survey. Water resources investigations 79-46. 

Raleigh, NC. 

 . 1985. Hydrology of major estuaries and sounds of North Carolina. United States 

Geological Survey. Water-supply paper 2221. Alexandria, Va. 

Hogarth, W. T. and K. L. Nichols. 1981. Brunswick Steam Electric Plant intake modifications to 

reduce entrainment and impingement losses. Carolina Power & Light Company, New Hill, NC. 

Lawler, J. P., M. P. Weinstein, H. Y. Chen and T. L. Englert. 1988. Modeling the physical and 

behavioral mechanisms influencing the recruitment of spot and Atlantic croaker to the Cape 

Fear Estuary. Am. Fish. Soc. Sym. 3: 115-131. 

PEC. 2005. Progress Energy Brunswick Steam Electric Plant proposal for information 

collection. NPDES Permit No. NC0007064. Progress Energy Carolinas Inc., Raleigh, NC. 
Brunswick Steam Electric Plant 2008 Biological Monitoring Report 

Progress Energy Service Company, LLC 3-2 Environmental Services Section

 . 2008. Brunswick Steam Electric Plant 2007 biological monitoring report. Progress Energy 

Carolinas Inc., Raleigh, NC. 

 . 2009. Brunswick Steam Electric Plant 2008 biological monitoring report. Progress Energy 

Carolinas Inc., Raleigh, NC. 

Schwartz, F. J., P. Perschbacher, L. Davidson, C. Simpson, D. Mason, M. McAdams, K. Sandoy 

and J. Duncan. 1979. An ecological study of fishes and invertebrate macrofauna utilizing the 

Cape Fear River Estuary, Carolina Beach Inlet, and adjacent Atlantic Ocean, 1973-1977. 

BSEP Cape Fear Studies, Volume XIV. Report to Carolina Power & Light Co., Institute of 

Marine Sciences, University of North Carolina, Morehead City, NC. 

Stone & Webster Engineering Corporation. 1984. Advanced intake technology study. Research 

project 2214-2. Prepared for the Electric Power Research Institute. Prepared by Stone & 

Webster Engineering Corporation. Boston, MA. 

Thompson, T. E. 1989. Factors limiting the movement of spot, Leiostomus xanthurus, into a 

freshwater-oligohaline tidal marsh. Master’s thesis. Department of Biological Sciences, 

University of North Carolina at Wilmington, Wilmington, N.C. 

Tomljanovich, D. A., J. H. Heuer, and C. W. Voigtlander. 1978. A concept for protecting fish 

larvae at water intakes. Trans. Amer. Fish. Soc. 30:105 - 106. 
Brunswick Steam Electric Plant 2009 Biological Monitoring Report 

Progress Energy Service Company, LLC A-1 Environmental Services Section

APPENDICES 

Appendix 1. Summary of historical environmental studies conducted in association with 

the Brunswick Steam Electric Plant, 1968-2009. 

As part of the initial nuclear licensing efforts Carolina Power & Light Company (CP&L, 

predecessor to Progress Energy Carolinas, Inc) commenced environmental impact studies in 

1968. Physical/chemical studies included dye and flow studies, water chemistry, and thermal 

studies. Biological studies included phytoplankton, zooplankton, benthos and larval fish and 

shellfish diversity, distribution and abundance studies in the main stem of the estuary. Juvenile 

and adult fish and shellfish population studies were also conducted in the estuary. Special 

emphasis was placed on Walden Creek and Snow’s Marsh adjacent to the plant’s intake canal. 

Entrainment and impingement studies were also conducted after Unit 2 came online in 1974. In 

addition, thermal tolerance, swimming performance studies and marsh productivity studies were 

conducted. 

Studies were expanded and intensified in 1976 to address the potential adverse impact on 

the entire estuary by the intake under full 2-unit operation. These comprehensive studies were 

developed through an interagency review group assembled at CP&L’s initiative and included 

representatives of the EPA, NRC, National Marine Fisheries Service, United States Fish and 

Wildlife Service, North Carolina Division of Marine Fisheries, North Carolina Division of 

Environmental Management (predecessor to NC DENR), the League of Women Voters, and 

CP&L. Exhaustive dye tracer, hydrographic, tidal, temperature, and salinity studies were 

conducted to model estuarine flow dynamics relative to plant intake flows. Various gear 

efficiency and sampling methodology studies were conducted to ensure that statistically valid 

data were collected. The biological studies were modified to provide adequate data concerning 

the larval, juvenile, and adult fish and shellfish populations having the greatest potential to be 

adversely affected by plant operation. In addition to weekly entrainment and impingement 

studies, population studies were conducted in the near-shore ocean, main stem estuary, estuarine 

shallows, and tidal creek nursery areas from below Southport, NC upstream to the vicinity of 

Wilmington, NC. Specific criteria studied included species composition plus spatial, seasonal, 

and inter-annual abundance as well as age, growth, dietary, and tagging studies. The principal 

investigators from CP&L, NCSU, Institute of Marine Science and Lawler, Matusky and Skelly 

consultants used results of these studies to determine the mechanisms by which larvae enter and 

are retained in this intensively flushed estuary and to provide insight regarding the lack of any 

detectable adverse environmental impact on fish and shellfish populations due to cooling water 

withdrawal. Results of these studies were compiled in the 20 volume Cape Fear Studies. 

Beginning in 1980 and continuing through 1993, CP&L conducted a long-term 

Biological Monitoring Program that would provide for the continued assessment of the impact 

that the cooling water withdrawal might have on the Cape Fear River Estuary. Using historic 

biological study results as a guide, particular emphasis was placed on marine fisheries. With 

some modification, these Biological Monitoring Studies were a continuation of the studies 

conducted since 1976, thus, allowing for long-term trending of results. Certain studies were also 

expanded or added to address the effectiveness of the circa 1983 intake modifications in reducing 

the number of organisms entrained and impinged. Beginning in 1984 a larval impingement 

study was conducted in addition to the standard entrainment and impingement studies as 
Brunswick Steam Electric Plant 2009 Biological Monitoring Report 

Progress Energy Service Company, LLC A-2 Environmental Services Section

Appendix 1. continued 

another means to assess the success of fine-mesh screens in reducing entrainment of larvae. 

Larval fish sampling was conducted in the ship channel and the mouths of two major tidal creek 

nursery areas. A larval fish discrete depth sampling study was conducted to better understand the 

distribution of larvae during recruitment to the estuary and to validate the standard larval fish 

study. A marsh nursery study using trawl, seine, and rotenone sampling was conducted to assess 

recruitment to and use of the tidal creek nursery areas with special interest placed on Walden 

Creek adjacent to the Plant’s intake canal and several nursery areas upstream of the intake canal. 

Sampling stations also included a location in the fish return basin. This station along with a 

special tagging study demonstrated that juvenile fish and shellfish used the return basin as a 

shallow water nursery area in a fashion similar to the headwaters of a natural tidal creek. A 

nekton study using trawl and gill net sampling was conducted to assess the populations of 

juvenile and adult fish and shellfish that could potentially be subject to impingement at the plant 

intake structure. Sampling stations in the CFE ranged from below Southport, NC to the vicinity 

of Wilmington, NC. Several sampling stations in the intake canal were used as an additional 

means of assessing the success of the fish diversion structure in reducing impingement. Survival 

studies were conducted in the fish return system to assess the success of the return system in 

returning larval, juvenile, and adult organisms alive to the estuary. A weekly temperature and 

salinity study was conducted along the main stem of the estuary since historic results indicated 

that freshwater flow, salinity, and temperature were the main determinants of fish and shellfish 

distribution and abundance in the estuary. 

Beginning in 1994 and continuing through the current permit cycle, the biological 

monitoring program was significantly reduced with the concurrence of State regulatory and 

resource agencies. Because of almost two decades of data demonstrating that the cooling water 

withdrawal has no adverse impact to the fish and shellfish populations in the estuary, the 

monitoring program was reduced to concentrate on entrainment and impingement only. This 

allowance was based on the fact that if the impingement mortality and entrainment performance 

remains relatively consistent then the environment remains protected. Sampling frequency was 

reduced to monthly sampling and results demonstrated the continuing effectiveness of the intake 

modifications in reducing entrainment and impingement of fish and shellfish. Periodic special 

study trawl surveys conducted in the marsh/tidal creek nursery areas continued to show no 

adverse impact on the recruitment to and use of these nursery areas by juvenile fish and shellfish. 

PEC believes over three decades of biological and environmental monitoring has resulted in one 

of the most extensive and informative data bases concerning our nation’s estuaries. These data 

can provide valuable insight regarding the ecology of our nation’s estuaries and any future phase 

II 316(b) regulations once the rule becomes finalized. 
Brunswick Steam Electric Plant 2009 Biological Monitoring Report 

Progress Energy Service Company, LLC A-3 Environmental Services Section

Appendix 2. Number+of larval organisms collected during entrainment and larval 

impingement sampling at the Brunswick Steam Electric Plant during 2009. 

 

Number 

collected 

Number 

collected 

Scientific name Common name entrainment impingement 

 

Gambusia holbrooki Eastern mosquitofish 0 1 

Elopidae Tarpons 

Elops saurus (leptocephalus) Ladyfish (leptocephalus) 1 43 

Megalops atlantica (leptocephalus) Tarpon (leptocephalus) 1 4 

Anguillidae Freshwater eels 

Anguillia rostrata American eel 2 3 

Ophichthidae Snake eels 0 0 

Myrophis punctatus (leptocephalus) Speckled worm eel 8 26 

Myrophis punctatus Speckled worm eel 2 12 

Ophichthus gomesi Shrimp eel 1 0 

Clupeidae Herrings 

Brevoortia tyrannus Atlantic menhaden 44 182 

Engraulidae Anchovies 

Anchoa spp. < 13 mm Anchovy larvae < 13 mm 785 653 

Anchoa spp. ≥ 13 mm Anchovy larvae ≥ 13 mm 684 2574 

A. mitchilli Bay anchovy 16 0 

A. hepsetus Striped anchovy 0 0 

Synodontidae Lizardfishes 

Synodus foetens Inshore lizardfish 0 3 

Ophidiidae Cusk-eels 

Ophidion welshi Crested cusk-eel 0 0 

Batrachoididae Toadfishes 

Opsanus tau Oyster toadfish 0 0 

Belonidae Needlefishes 

Strongylura marina Atlantic needlefish 0 0 

Exocoetidae Flying fishes 

Hyporhamphus unifasciatus Silverstripe halfbeak 0 5 

Cyprinodontidae Killifishes 

Cyprinodon variegates Sheepshead minnow 0 0 

Fundulus heteroclitus Mummichog 5 1 

Fundulus majalis Striped killifish 0 0 

Poeciliidae Livebearers 

Poecilia latipinna Sailfin molly 0 0 

Gadidae Codfishes 

Urophycis floridana Southern hake 0 0 

Atherinidae Silversides 206 28 

 Menidia beryllina Inland silverside 1 0 

Menidia menidia Atlantic silverside 0 0 

Syngnathidae Pipefishes and seahorses 

Syngnathus spp. Unidentified pipefish 3 0 

S. fuscus Northern pipefish 1 4 

S. louisianae Chain pipefish 2 13 

Hippocampus erectus Lined seahorse 0 0 

Triglidae Searobins 

Prionotus spp. Searobin 3 15 

P. carolinus Northern searobin 0 0 

P. tribulus Bighead searobin 0 0 

Serranidae Seabasses 

Mycteroperca spp. Grouper 0 2 
Brunswick Steam Electric Plant 2009 Biological Monitoring Report 

Progress Energy Service Company, LLC A-4 Environmental Services Section

Appendix 2 continued 

Number 

collected

Number 

collected

Scientific name Common name entrainment impingement

 

Percichthyidae Temperate basses 

Morone spp. Temperate bass 7 0 

Carangidae Jacks 2 6 

Caranx hippos Crevalle jack 0 0 

Chloroscombrus chrysurus Atlantic bumper 0 1 

Selene vomer Lookdown 0 1 

Trachinotus carolinus Florida pompano 0 0 

T. falcatus Permit 0 0 

Oligoplites saurus Leatherjacket 0 0 

Lutjanidae Snappers 0 0 

Lutjanus griseus Gray snapper 0 6 

Lutjanus synagris Lane snapper 0 2 

Centrachidae Sunfishes 

Lepomis spp. Sunfish larva 0 0 

Gerridae Mojarras 5 8 

Haemulidae Grunts 0 0 

Orthopristis chrysoptera Pigfish 5 89 

Sparidae Porgies 

Lagodon rhomboides Pinfish 19 155 

Archosargus probotocephalus Sheepshead 0 0 

Sciaenidae Drums 

Bairdiella chrysoura Silver perch 12 38 

Cynoscion nebulosus Spotted seatrout 22 3 

C. regalis Weakfish 2 20 

Leiostomus xanthurus Spot 512 2750 

Menticirrhus spp. Kingfish spp. 2 5 

Micropogonias undulatus Atlantic croaker 278 2879 

Sciaenops ocellatus Red drum 3 5 

Pogonias cromis Black drum 4 1 

Stellifer lanceolatus Star drum 0 1 

Ephippidae Spadefishes 

Chaetodipterus faber Atlantic spadefish 0 0 

Mugilidae Mullets 

Mugil cephalus Striped mullet 19 123 

M. curema White mullet 1 3 

Sphyraenidae Barracudas 

S. borealis Northern sennet 0 0 

Uranoscopidae Stargazers 

Astroscopus guttatus Northern stargazer 0 1 

Blenniidae Combtooth blennies 60 2 

Eleotridae Sleepers 

Dormitator maculatus Fat sleeper 0 1 

Eleotris pisonis Spinycheek sleeper 0 1 

Gobiidae Gobies 

Gobionellus spp. Goby 23 137 

Gobiosoma spp. Goby 716 823 

Microgobius spp. Goby 60 65 

Trichiuridae Snake mackerels 

Trichiurus lepturus Atlantic cutlassfish 0 0 

Stromateidae Butterfishes 

Peprilus alepidotus Harvestfish 1 0 
Brunswick Steam Electric Plant 2009 Biological Monitoring Report 

Progress Energy Service Company, LLC A-5 Environmental Services Section

Appendix 2 continued 

Number 

collected

Number 

collected

Scientific name Common name entrainment impingement

 

Stromateidae Butterfishes 

P. triacanthus Butterfish 0 0 

 

Bothidae Lefteye flounders 

Citharichthys spp. Whiff larvae 0 15 

Paralichthys spp. larvae Flounder larvae 4 38 

Soleidae Soles 

Trinectes maculatus Hogchoker 5 12 

Gobiesocidae Clingfishes 

Gobiesox strumosus Skilletfish 4 1 

Cynoglossidae Tonguefishes 

Symphurus spp. Tonguefish larvae 3 13 

Symphurus plagiusa Blackcheek tonguefish 1 0 

Balistidae Filefishes 

Monacanthus hispidus Planehead filefish 0 28 

Tetraodontidae Puffers 

Spheroides maculatus Northern puffer 0 0 

Chilomycterus schoepfi Striped burrfish 0 1 

 

Invertebrates 

 

Penaeidae Shrimp 

Penaeid shrimp larvae, postlarvae stage 

Shrimp larvae 

(pink, brown, white) 301 6772 

Farfantepenaeus aztecus Brown shrimp 0 3 

F. duorarum Pink shrimp 0 5 

Litopenaeus setiferus White shrimp 0 6 

Trachypeneus constrictus T-con or hardback shrimp 29 1577 

Portunidae Swimming crabs 

Portunid crab < 10 mm Swimming crabs 5 628 

Portunid crab larvae, megalops stage Swimming crab megalops 110 1911 

Callinectes spp. < 20 mm Unidentified Callinectes crab 0 55 

 

Total organisms 3,983 21,760 

 

+

Numbers represent total number collected per 5-minute sample summed over all samples. 
Brunswick Steam Electric Plant 2009 Biological Monitoring Report 

Progress Energy Service Company, LLC A-6 Environmental Services Section

Appendix 3. Number+ and biomass (g) of juvenile and adult organisms collected during 

impingement sampling at the Brunswick Steam Electric Plant during 2009. 

 Total Total 

Scientific name Common name number weight (g) 

 

Carcharhinidae Sharks 

Rhizoprionodon terraenovae Atlantic sharpnose shark 5 1436 

Dasyatidae Skates and Rays 

Dasyatis americana Southern stingray 0 0 

D. sabina Atlantic stingray 9 1445 

Gymnura micrura Smooth butterfly ray 28 6024 

Anguillidae Freshwater eels 

Anguilla rostrata American eel 0 0 

Elopidae Tarpons 

Elops saurus Ladyfish 1 26 

Ophichthidae Snake eels 

Myrophis punctatus Speckled worm eel 155 1965 

Ophichthus gomesi Shrimp eel 72 3166 

Clupeidae Herrings 

Alosa aestivalis Blueback herring 17 35 

A. sapidissima American shad 77 366 

Brevoortia tyrannus Atlantic menhaden 1494 20662 

Dorosoma cepedianum Gizzard shad 0 0 

D. petenense Threadfin shad 1154 4934 

Opisthonema oglinum Atlantic thread herring 100 600 

Engraulidae Anchovies 

Anchoa hepsetus Striped anchovy 680 3962 

Anchoa mitchilli Bay anchovy 73628 77125 

Synodontidae Lizardfishes 

Synodus foetens Inshore lizardfishes 12 367 

Gadidae Codfishes 

Urophycis floridana Southern hake 4 22 

U. regia Spotted hake 73 566 

Ophidiidae Cusk-eels 

Ophidion welshi Crested cusk-eel 6 42 

Batrachoididae Toadfishes 

Opsanus tau Oyster toadfish 33 1241 

Gobiesocidae Clingfishes 

Gobiesox strumosus Skilletfish 0 0 

Exocoetidae Flying fishes 

 Hemiramphus brasiliensis Ballyhoo 18 6 

Hyporhamphus unifasciatus Silverstripe halfbeak 112 168 

Belonidae Needlefishes 

Strongylura marina Atlantic needlefish 0 0 

Cyprinodontidae Killifishes 

Fundulus heteroclitus Mummichog 14 29 

Fundulus majalis Striped killifish 0 0 

Atherinidae Silversides 

Membras martinica Rough silverside 1027 1777 

Menidia menidia Atlantic silverside 123 263 

Fistulariidae Cornetfishes 

Fistularia tabacaria Bluespotted cornetfish 0 0 

Syngnathidae Pipefishes 

Syngnathus fuscus Northern pipefish 163 291 

Syngnathus louisianae Chain pipefish 168 427 
Brunswick Steam Electric Plant 2009 Biological Monitoring Report 

Progress Energy Service Company, LLC A-7 Environmental Services Section

Appendix 3 continued 

Total Total 

Scientific name Common name number weight (g) 

 

Hippocampus erectus Lined seahorse 0 0 

Scorpaenidae Scorpionfishes 

Scorpaena sp. Scorpionfish 0 0 

Triglidae Searobins 

Prionotus evolans Striped searobin 1 16 

Prionotus scitulus Leopard searobin 14 73 

Prionotus tribulus Bighead searobin 174 795 

Serranidae Sea basses 

Mycteroperca microlepis Gag 0 0 

Centropristis striata Black seabass 0 0 

Pomatomidae Bluefishes 

Pomatomus saltatrix Bluefish 41 298 

Rachycentridae Cobia 

Rachycentron canadum Cobia 7 44 

Carangidae Jacks 

Caranx hippos Crevalle jack 0 0 

Chloroscombrus chrysurus Atlantic bumper 10 242 

Oligoplites saurus Leatherjack 0 0 

Selene vomer Lookdown 40 437 

Trachinotus falcatus Permit 10 58 

Lutjanidae Snappers 

Lutjanus griseus Gray snapper 2 8 

Lobotidae Tripletails 

Lobotes surinamensis Tripletail 0 0 

Centrachidae Sunfishes 

Lepomis macrochirus Bluegill 0 0 

Gerridae Mojarras 

Diapterus auratus Irish pompano 0 0 

Eucinostomus argenteus Spotfin mojarra 12 136 

Haemulidae Grunts 

Orthopristis chrysoptera Pigfish 18 161 

Sparidae Porgies 

Archosargus probatocephalus Sheepshead 4 40 

Lagodon rhomboides Pinfish 382 1960 

Sciaenidae Drums 

Bairdiella chrysoura Silver perch 323 2311 

Cynoscion nebulosus Spotted seatrout 2 2723 

C. regalis Weakfish 60 325 

Larimus fasciatus Banded drum 0 0 

Leiostomus xanthurus Spot 8776 74509 

Menticirrhus americanus Southern kingfish 0 0 

M. saxatilis Northern kingfish 0 0 

Micropogonias undulatus Atlantic croaker 2120 32056 

Sciaenops ocellatus Red drum 21 32 

Stellifer lanceolatus Star drum 468 1630 

Ephippidae Spadefishes 

Chaetodipterus faber Atlantic spadefish 1 30 

 Chaetodontidae Butterfly fishes 

Chaetodon ocellatus Spotfin butterflyfish 0 0 

Mugilidae Mullets 

Mugil cephalus Striped mullet 39 653 

M. curema White mullet 2 33 
Brunswick Steam Electric Plant 2009 Biological Monitoring Report 

Progress Energy Service Company, LLC A-8 Environmental Services Section

Appendix 3 continued 

Total Total 

Scientific name Common name number weight (g) 

 

Sphyraenidae Barracudas 

Sphyraena barracuda Great barracuda 0 0 

S. borealis Northern sennet 0 0 

Labridae Wrasses 

Tautoga onitis Tautog 0 0 

Uranoscopidae Stargazers 

Astroscopus guttatus Northern stargazer 0 0 

A. y-graecum Southern stargazer 0 0 

Blenniidae Combtooth blennies 

Chasmodes bosquianus Striped blenny 5 26 

Hypsoblennius hentz Feather blenny 9 157 

H. ionthas Freckled blenny 0 0 

Eleotridae Sleepers 

Eleotris pisonis Spinycheek sleeper 0 0 

Gobiidae Gobies 

Gobionellus oceanicus Highfin goby 0 0 

Gobiosoma bosc Naked goby 7 22 

Microdesmidae Wormfishes 

Microdesmus longipinnis Pink wormfish 0 0 

Trichiuridae Snake mackerels 

Trichiurus lepturus Atlantic cutlassfish 134 1959 

Scombridae Mackerels 

Scomberomorus maculatus Spanish mackerel 0 0 

Stromateidae Butterfishes 

Peprilus alepidotus Harvestfish 39 567 

P. triacanthus Butterfish 0 0 

Bothidae Lefteye flounders 

Ancylopsetta quadrocellata Ocellated flounder 42 312 

Citharichthys spilopterus Bay whiff 294 2565 

Etropus crossotus Fringed flounder 477 3430 

Paralichthys dentatus Summer flounder 35 133 

P. lethostigma Southern flounder 4 1172 

Scophthalmus aquosus Windowpane 0 0 

Soleidae Soles 

Trinectes maculatus Hogchoker 26 154 

Cynoglossidae Tonguefishes 

Symphurus plagiusa Blackcheek tonguefish 2098 9069 

Balistidae Triggerfishes and filefishes 

Monacanthus hispidus Planehead filefish 0 0 

Aluterus schoepfi Orange filefish 0 0 

Tetraodontidae Puffers 

Chilomycterus schoepfi Striped burrfish 2 195 

Sphoeroides maculates Northern puffer 44 1535 

 

Invertebrates Mollusks, shrimps, and crabs 

 

Aphysiidae Sea hares 

Aplysia sp. Sea hare 0 0 

Lologinidae Sea hares 

Lolliguncula brevis Brief squid 265 1922 

Limulidae Horseshoe crabs 

Limulus polyphemus Horseshoe crab 1 1360 
Brunswick Steam Electric Plant 2009 Biological Monitoring Report 

Progress Energy Service Company, LLC A-9 Environmental Services Section

Appendix 3 continued 

Total Total 

Scientific name Common name number weight (g) 

 

Squillidae Mantis shrimps 

Squilla empusa Mantis shrimp 51 855 

Alpheidae Snapping shrimps 

Alpheus sp. Snapping shrimp 9 9 

Sicyoniidae Rock shrimps 

Sicyonia sp. Rock shrimp 0 0 

Penaeidae Prawns 

Farfantepenaeus aztecus Brown shrimp 3172 21219 

F. duorarum Pink shrimp 954 2017 

Litopenaeus setiferus White shrimp 11778 79774 

Trachypeneus constrictus T-con or hardback shrimp 328 282 

Portunidae Swimming crabs 

Ovalipes sp. Lady crab 0 0 

Portunus sp. Swimming crabs 76 323 

P. spinimanus Brown bar crab 93 176 

Callinectes ornatus Shelligs crab 293 1027 

C. sapidus Blue crab 1037 21805 

C. similus Lesser blue crab 965 3118 

Eurypanopeus abbreviatus Mud crab 19 276 

Reptiles 

 

Emydidae Emydiaeid turtles 

Malaclemys terrapin Diamondback terrapin 2 188 

 

Total organisms 113,959 401,161 

 

+

Numbers and biomass represent total number and weight collected per 24-hour sample summed 

over all sample dates.